The embodiments herein relate to methods and compositions for proppant suspension and consolidation in subterranean treatment operations.
Subterranean wells (e.g., hydrocarbon producing wells) are often stimulated by hydraulic fracturing treatments. In hydraulic fracturing treatments, a treatment fluid is pumped into a portion of a subterranean formation at a rate and pressure such that the subterranean formation breaks down and one or more fractures are formed. Typically, particulate solids, such as graded sand, are suspended in a portion of the treatment fluid and then deposited into the fractures. These particulate solids, or “proppant particulates,” serve to prop the fracture open (e.g., keep the fracture from fully closing) after the hydraulic pressure is removed. By keeping the fracture from fully closing, the proppant particulates aid in forming conductive paths through which produced fluids, such as hydrocarbons, may flow.
The degree of success of a fracturing operation depends, at least in part, upon fracture porosity and conductivity once the fracturing operation is complete and production has begun. Thus, the proppant particulates should be substantially evenly distributed throughout the treatment fluid such that a sufficient number of the proppant particulates are placed within a fracture to prop the fracture open. For this reason, viscosified treatment fluids are typically used to place proppant particulates into a fracture in a subterranean formation because the viscous nature of the treatment fluid is capable of maintaining the proppant particulates in suspension, thereby reducing their tendency to settle out of the treatment fluid prior to reaching the fracture or other desired placement zone.
Once placed inside a fracture, the distribution of the proppant particulates creates a permeable medium, or a “proppant pack,” through which production fluids flow from the formation and into the wellbore for collection at the surface. As the production fluids flow through the interstitial spaces between adjacent proppant particulates in the proppant pack, insufficiently bound or loose proppant particulates will be entrained with the production fluid and produced into the wellbore, termed “proppant flowback.” Proppant flowback may be particularly detrimental to subterranean formation operations and equipment, as the proppant particulates flow into the wellbore and to the surface eroding metal goods, plugs, piping, valves, instruments, and other production equipment. Moreover, additional time and equipment expense is necessary to remove the proppant particulates from desired production fluids.